KR20060033799A - Colour tunable lighting element - Google Patents

Abstract

A colour tunable lighting element is described, which comprises an assembly of dielectric barrier discharge lamps, each of them filled with a noble gas or a noble gas mixture, wherein a Xe low-pressure discharge generates invisible UV radiation, which is converted into visible light by one or several phosphors being coated onto the inner surface of the bulb, wherein the visible light of several dielectric barrier discharge lamps is mixed by optical means and is emitted homogeneously. Such an assembly of dielectric barrier discharge lamps is useful for the generation of white light with an arbitrary colour temperature and of saturated coloured light.

Description

Color adjustable lighting element {COLOUR TUNABLE LIGHTING ELEMENT}

The present invention provides an assembly of dielectric barrier discharge lamps in which invisible UV-radiation is converted into visible light by one or several phosphors coated on the inner surface of the bulb. It relates to a color control lighting device comprising.

Lighting devices that emit diffuse plane rays are widely used today. These developments are focused on improving color variability. By using several color lamps in one housing, the light rays of these lamps can be mixed by optical means, and the color points of the light rays emitted from the lighting elements by adjusting the ratio of the colors used. Can be changed. This effect may be implemented with other types of lamps, but if so, it is still a situation to bear various disadvantages, the present invention is to solve this problem.

An inherent disadvantage of conventional lighting systems is that the color lamps do not emit saturated colors due to the content of the visible mercury spectrum, which limits the color gamut obtainable. Moreover, such lamps are dimmable to a certain extent, which is a disadvantage in the use of the lamps.

When used as an LED instead of a lamp, it is possible to obtain a saturated primary color. However, due to the low half-width of the LED's emission band, in order to reproduce the complete CIE color triangle, many different LEDs (red, green, blue, orange-yellow, cyan) must be used. Moreover, in terms of currently available LEDs, the light yield is still low, which means that a large number of LEDs must be used to achieve sufficient brightness. This is causing an increase in the cost of LED-based systems.

Although electric light bulbs can be used with color filters, they are also quite inefficient, resulting in high power losses and the associated heat removal problem.

Therefore, there is a need for systems with characteristics such as high color saturation, compact design, full dimmability, sufficient lifetime, good efficiency, and competitive price per lumen.

Currently no system fully satisfies these conditions.

The present invention is based on the use of dielectric barrier discharge lamps containing noble gases for light-tiles or emitters of variable light color. This takes advantage of many of the noble gas dielectric barrier discharge lamps.

An object of the present invention is a color adjustable illumination element, comprising an assembly of dielectric barrier discharge lamps, each filled with a rare gas or rare gas mixture, wherein the low mercury low pressure discharge produces invisible UV radiation, which is the inner surface of the bulb The visible light is converted into visible light by one or several phosphors coated on it, and the visible light of several dielectric barrier discharge lamps is mixed by optical means and emitted homogeneously.

Particularly preferred lighting elements according to the invention are rare gas mixtures containing xenon and neon. These lighting elements emit almost exclusively UV light, which is converted into visible light by the phosphor.

If pure xenon (Xe ₂ ^* -excimer-discharge) is used, UV light with wavelengths of 172 nm and 150 nm is emitted, which means that the plasma is virtually invisible. The mixture of neon is advantageous because it reduces the illumination voltage of the discharge lamp from 2 kW to 200 V depending on the content of the neon (Penning-Effect). This allows the use of currently available electronic driver units for neon discharge lamps. However, the xenon ratio should be at least 10%, otherwise the xenon's resonance line should be radiated between 580 nm and 700 nm. This will significantly reduce the clarity of the color of the blue, green or red lamps. In any case, high concentration neon may be used for these lamps emitting in the red region of the spectrum.

Since the spectrum of the xenon excimer plasma does not contain visible light, depending on the nature of the phosphor used, the lamp emits colored light which is determined only by the emission of the phosphor. Thus, by selecting a suitable phosphor (see FIG. 8), very high saturation can be obtained. Xenon or xenon / neon discharge (147 nm, 150 nm, 172 nm) phosphors that efficiently convert radiation of invisible light are listed in Table 1.

A preferred embodiment of the present invention is a color adjustable illumination element, comprising an assembly of several dielectric barrier discharge lamps that emit red, green or blue light rays, the lamp comprising:

Red: (Y, Gd) BO ₃ : Eu, Y ₂ O ₃ : Eu, Y (V _{1 -x- y} P _x Nb _y ) O ₄ : Eu,

_{GdMgB 5 O 10: Ce, Mn} , Mg 4 GeO 5 .5 F: Mn

Green: BaMgAl ₁₀ O ₁₇ : Eu, Mn, BaAl ₁₂ O ₁₉ : Mn, Zn ₂ SiO ₄ : Mn,

LaPO ₄ : Ce, Tb, (Y _{1 - x} Gd _x ) BO ₃ : Tb, InBO ₃ : Tb

Blue: Sr ₂ P ₂ O ₇ : Eu, BaMgAl ₁₀ O ₁₇ : Eu,

(Y _{1 - x} Gd _x ) BO ₃ : Ce, (Y _{1 - x} Gd _x ) (V _{1 - y} P _y ) O ₄

One or several phosphors selected from.

Another preferred color adjustable lighting element comprises an assembly of several dielectric barrier discharge lamps that emit blue or yellow light, the lamp comprising:

Blue: BaMgAl ₁₀ O ₁₇ : Eu, (Y _{1 - x} Gd _x ) BO ₃ : Ce, (Y _{1 - x} Gd _x ) (V _{1 - y} P _y ) O ₄

Yellow: (Y _{1 - x} Gd _x ) ₃ Al ₅ O ₁₂ : Ce, (Y _{1 - x} Gd _x ) ₃ (Al _{1 - y} Ga _y ) ₅ O ₁₂ : Ce

One or several phosphors selected from.

Another preferred embodiment of the present invention is a color adjustable illumination element, comprising an assembly of several dielectric barrier discharge lamps emitting a cyan or orange light, the lamp comprising:

Cyan: BaMgAl ₁₀ O ₁₇ : Eu, Mn

Orange: (Sc _{1 - x} Lu _x ) BO ₃ : Eu, (In _{1 - x} Gd _x ) BO ₃ : Eu

One or several phosphors selected from.

The lighting elements according to the invention are considerably more efficient than electric light bulbs with color filters because their energy efficiency reaches 5% to 15%. As the discharge of the lamp occurs at a very short distance, the shape of the lamp can be designed in a wide variety. It may be in the form of a thin tube or may be in the form of a plate with a large surface. Because of these characteristics, electrically variable discharge lamps are well suited as color adjustable illumination elements.

Another advantage of the lighting element according to the invention is that the brightness of each single dielectric barrier discharge lamp can be varied independently, which makes it possible to individually adjust the emission color of the lighting element as needed. Furthermore, by using suitable optical filter means, the resulting color of the emitted light can be adjusted to produce white light.

The invention is explained below by means of the accompanying drawings.

1 is BaMgAl ₁₀ O ₁₇ and a phosphor _{(Y 1 - x Gd x)} 3 Al 5 O 12: a diagram showing the spectrum of the light tile (tile light) including a xenon dielectric barrier discharge lamp having a Ce.

FIG. 2 shows color triangles with adjustable color points of optical tiles with xenon dielectric barrier discharge lamps. FIG.

FIG. 3 shows the spectrum of an optical tile comprising a xenon dielectric barrier discharge lamp with BaMgAl ₁₀ O ₁₇ Eu, (Y, Gd) BO ₃ : Tb and (Y, Gd) BO ₃ : Eu as phosphors. FIG. .

4 is an optical tile with a xenon dielectric barrier discharge lamp coated with BaMgAl ₁₀ O ₁₇ Eu (BAM), (Y, Gd) BO ₃ : Tb (YGBT) or (Y, Gd) BO ₃ : Eu (YGBE) A diagram showing chromatic triangles with their adjustable chromatic points.

FIG. 5 shows an optical tile with a “channel-lit backlight” comprising several clusters each composed of xenon dielectric barrier discharge lamps emitting red, green and blue light.

FIG. 6 shows an optical tile with a "channel-lighted backlight" comprising several clusters, each with a xenon dielectric barrier discharge lamp emitting yellow and blue.

FIG. 7 shows an optical tile with a “side-lit backlight” comprising several clusters each having a xenon dielectric barrier discharge lamp emitting yellow and blue.

8 shows the color points of a xenon dielectric barrier discharge lamp for use as a primary light source in the light tiles of FIGS. 6-8.

Table 2 is a table showing an abbreviation list of phosphors used in FIG. 8.

First Example

Blue and yellow Radiating  Optical tile with xenon dielectric barrier discharge lamp

Cavity-lit photo tiles as shown in FIG. 6 have an assembly of dielectric barrier discharge lamps that emit blue and yellow light rays. The blue lamp is coated with BaMgAl ₁₀ O ₁₇ : Eu (BAM) as a phosphor by the conventional Up-Flush-Coating-Process, and the yellow lamp is (Y _{1 - x} Gd _x ) ₃ Al ₅ O ₁₂ : coated with Ce (YAG). The spectrum of this light tile is shown in FIG. 1.

Each lamp of such a light tile can be effect controlled by a separate driver so that the brightness of the lamp can be adjusted individually. It is thus possible to adjust each color point located on a line defined by the color coordinates of the two color dielectric barrier discharge lamps (see FIG. 2).

The color points of the adjustment shown in FIG. 1 are at x = 0,346 and y = 0,400, ie the color temperature is about 5100K. In this adjustment, the color rendering is at R _a = 70.

With the assembly of this embodiment, all the color points located on the line between the color points of the BAM lamp and the YAG lamp of Fig. 2 can be adjusted by dimming.

The ray color of the light tile may be affected by the dimming of the xenon dielectric barrier discharge lamp, but only the ray color within the color range defined by the primary color of the different color lamps can only be reproduced accordingly.

If the yellow lamp is changed, a light tile can be implemented that also allows adjustment of lower color temperatures. To this end, the yellow lamp _{(Y 1 - x Gd x)} 3 Al 5 O 12: Ce (YAG) , and YVO _4: Eu (YVE) or _{Y (V 1 -x- y P x} Nb y) O 4: Coated with a phosphor mixture consisting of Eu (YVPE). Depending on the mixing ratio, the color points are located on the line defined by the color points of the BAM and YAG / YVE or YAG / YVPE mixtures.

2nd Example

Red, green and blue Radiating  Optical tile with xenon dielectric barrier discharge lamp

The co-illuminated light tile as shown in FIG. 5 has an assembly of dielectric barrier discharge lamps emitting red, green and blue. By a conventional up-flush-coating process the blue lamp is coated with BaMgAl ₁₀ O ₁₇ : Eu (BAM) as a phosphor, green is (Y, Gd) BO ₃ : Tb (YGBT) and red is (Y, Gd ) Is coated with BO ₃ : Eu (YGBE).

Each lamp is controlled by an individual driver so that the brightness of each lamp can be adjusted individually. This allows the adjustment of each color point located within the color triangle defined by the color coordinate of each color dielectric barrier discharge lamp.

FIG. 3 shows that the color point of the light tile at x = 0,325 and y = 0,305, i.e., the color temperature is about 5900 K. FIG. Color regeneration (colour reproduction) from the adjustment (adjustment) is in the R _a = 87. With this assembly, all color points located within the triangle defined by the color points of the BAM lamp, YGBT lamp and YGBE lamp as shown in FIG. 4 can be adjusted by dimming.

FIG. 4 illustrates the color triangles mentioned in the description of FIG. 3.

FIG. 5 shows light with a "channel-lit-backlight" consisting of a light distributor plate comprising several clusters of xenon dielectric barrier discharge lamps emitting red, green and blue light. Show the tile. The light distribution plate is covered with a diffuser and uncoupling plate.

FIG. 6 shows an optical tile with a "channel-illumination-backlit" consisting of a light distribution plate with several clusters each composed of xenon dielectric barrier discharge lamps emitting yellow and blue. The light distribution plate is covered with a diffuser and an unbound plate.

FIG. 7 consists of a light distribution plate having clusters of yellow and blue emitting xenon dielectric barrier discharge lamps located on opposite sides of the light distribution plate covered by the diffuser and the unbound plate. -lit) shows a light tile with a backlight.

FIG. 8 shows the color points of a xenon dielectric barrier discharge lamp for use as a primary light source in the tiles of FIGS. 6-8.

Claims (7)

Color tuneable lighting element, Dielectric barrier discharge lamps, each of which comprises an assembly of noble gas or a rare gas mixture, Xenon excimer discharge produces invisible UV radiation, which is converted into visible light by one or several phosphors coated on the inner surface of the bulb, And the visible light of the several dielectric barrier discharge lamps is mixed by optical means to emit homogeneously. The method of claim 1, An assembly of several dielectric barrier discharge lamps emitting red, green or blue light, The lamp, Red: (Y, Gd) BO ₃ : Eu, Y ₂ O ₃ : Eu, Y (V _{1 -x- y} P _x Nb _y ) O ₄ : Eu, _{GdMgB 5 O 10: Ce, Mn} , Mg 4 GeO 5 .5 F: Mn Green: BaMgAl ₁₀ O ₁₇ : Eu, Mn, BaAl ₁₂ O ₁₉ : Mn, Zn ₂ SiO ₄ : Mn, LaPO ₄ : Ce, Tb, (Y _{1 - x} Gd _x ) BO ₃ : Tb, InBO ₃ : Tb Blue: Sr ₂ P ₂ O ₇ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, (Y _{1 - x} Gd _x ) BO ₃ : Ce, (Y _{1 - x} Gd _x ) (V _{1 - y} P _y ) O ₄ Color adjustable illumination element with one or several phosphors selected from. The method of claim 1, An assembly of several dielectric barrier discharge lamps emitting blue or yellow light, The lamp, Blue: BaMgAl ₁₀ O ₁₇ : Eu, (Y _{1 - x} Gd _x ) BO ₃ : Ce, (Y _{1 - x} Gd _x ) (V _{1 - y} P _y ) O ₄ Yellow: (Y _{1 - x} Gd _x ) ₃ Al ₅ O ₁₂ : Ce, (Y _{1 - x} Gd _x ) ₃ (Al _{1 - y} Ga _y ) ₅ O ₁₂ : Ce Color adjustable illumination element with one or several phosphors selected from. The method of claim 1, An assembly of several dielectric barrier discharge lamps emitting a cyan or orange ray, The lamp, Cyan: BaMgAl ₁₀ O ₁₇ : Eu, Mn Orange: (Sc _{1 - x} Lu _x ) BO ₃ : Eu, (In _{1 - x} Gd _x ) BO ₃ : Eu Color adjustable illumination element with one or several phosphors selected from. The method according to any one of claims 1 to 4, The brightness of each of said lamps can be independently varied by means of a suitable electronic driver unit. The method according to any one of claims 1 to 5, And the brightness of the lamp is varied by suitable optical filter means in such a way that the resulting color of the emitted light becomes white. Use of the dielectric barrier discharge lamp assembly of any one of claims 1 to 6 for the generation of saturated colored light rays.

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